vn] DISPUTED QUESTIONS 95 



been confirmed there are other possible explanations 

 of the apparent transmission of the effects of injury. 

 For example, Brown-S^quard found that when the 

 chief nerve of the leg is severed, the toes become 

 morbid and the animals frequently nibble them away. 

 A small percentage of the offspring of guinea-pigs 

 lacking toes from this cause also had toes missing. 

 But it has been pointed out that rodents in captivity 

 sometimes eat off the toes or tails of their young, and 

 if the mother had acquired the habit of nibbling her 

 own toes, she might bite off those of her young 

 shortly after birth and give the appearance of the 

 inheritance of a mutilation [20, 29]. Evidence has 

 also been brought forward that the mutilation of the 

 parents may cause the production of a toxin, which 

 is transmitted directly to the offspring, and causes 

 abnormalities to appear in them in the same organs 

 that were injured in the parent. 



Quite recently Kammerer [19] in Vienna has made 

 some remarkable observations on salamanders and 

 a species of toad which seem to support the idea of 

 the inheritance of acquired characters. For example, 

 among other experiments, he finds that the animals 

 can be accustomed to lay their eggs in water instead 

 of on land, and the young become modified to suit 

 their new surroundings, and the modifications are 

 progressively increased in later generations. He 

 points out however that most of his results, like 



